Network problem

[Willis Taylor]

I have two units running Ubuntu v. 7.10.  I have a Linksys hub connected 
to the ADSL router and both units are connected to the hub.  Both have 
unlimited internet access but neither one sees the other.  I have 
enabled sharing of the pictures file but when I type in the search 
172.xx.x.33 on one or 172.xx.x.36 on the other followed by /pictures it 
accesses the native file and not the one on the other unit.

Any help?